The British government has announced plans to build up to 12 new conventionally-armed, nuclear-powered submarines as part of the AUKUS programme, marking a significant shift in its naval posture. The move comes alongside the publication of the UK’s new Strategic Defence Review (SDR), which outlines a series of recommendations aimed at preparing the armed forces for evolving global threats.
Currently operating seven Astute-class attack submarines, the UK will begin replacing these vessels with SSN-AUKUS class boats starting in the late 2030s. This expansion represents a key element in a broader defence strategy that also includes major investment in the country’s nuclear warhead programme and enhanced readiness across multiple military domains.
The upcoming submarine builds are expected to be carried out at industrial sites in Barrow-in-Furness and Raynesway, Derby, with the government aiming to deliver one new submarine every 18 months. To meet this target, officials say the defence and civil nuclear sectors will undergo significant workforce development, including 30,000 apprenticeships and 14,000 graduate roles over the next decade.
In parallel, a £15 billion investment has been allocated to modernise the UK’s sovereign nuclear warhead infrastructure, with upgrades planned for the Atomic Weapons Establishment in Aldermaston. This investment is intended to support more than 9,000 jobs at the site and additional employment throughout the national supply chain.
The SDR outlines 62 recommendations, all of which the government is expected to adopt. These include measures to increase stockpiles of munitions, enhance digital and cyber capabilities through the creation of a new CyberEM Command, and improve service housing through more than £1.5 billion in additional funding.
Defence Secretary John Healey noted that the expansion of the submarine fleet and warhead programme reflects a response to a changing global security environment, including increased Russian military activity. He added that the initiatives are also tied to long-term workforce and industrial policy objectives.
The UK’s continued participation in the AUKUS defence partnership with the United States and Australia remains a central component of its Indo-Pacific strategy, while the new submarine fleet is expected to contribute to NATO’s deterrence posture in the Euro-Atlantic region.
Government officials have also confirmed a goal to raise defence spending to 2.5% of GDP by 2027, with an aspiration to reach 3% in the future depending on economic conditions.
The Strategic Defence Review signals a recalibration of UK defence priorities, with a strong emphasis on readiness, industrial capability, and workforce expansion as key pillars of national security planning.